refactor(M03): extract M2 mesh resource cache state

Work-Package: M03-RND-M2-MESH-RESOURCE-CACHE-001
Agent: sindo-main-codex
Tests: 35 headless renderer/coordinate contracts pass; checkpoint dry-run 7/7; documentation and coordination gates pass
Fidelity: preserves exact Mesh references, replacement semantics and final-shutdown lifetime; no visual parity claim

coordination/claims/M03-RND-M2-MESH-RESOURCE-CACHE-001.md

@@ -30,6 +30,8 @@ all existing cache consumers.
   `src/tools/verify_m2_mesh_resource_cache_state.gd`,
   `docs/modules/m2-mesh-resource-cache-state.md`, this claim
 - Shared/hotspots: `src/scenes/streaming/streaming_world_loader.gd`,
+  `src/tools/verify_m2_mesh_load_pipeline_state.gd`,
+  `src/tools/verify_render_runtime_cache_shutdown.gd`,
   `docs/modules/world-renderer.md`, `docs/modules/README.md`, `RENDER.md`,
   `targets/03-renderer-facade.md`
 - Generated/ignored: `.godot`, native DLL, generated M2 resources, caches and